From 1f3178e7433ed28d65bdb0f0219334e8dfc90c69 Mon Sep 17 00:00:00 2001
From: OJ Kwon <1210596+kwonoj@users.noreply.github.com>
Date: Fri, 17 Nov 2023 12:59:01 -0800
Subject: [PATCH] fix(next-core): allow runtime segment option in pages/api
 (#58409)

### What

This PR fixes turbopack to allow runtime segment option (https://nextjs.org/docs/app/building-your-application/rendering/edge-and-nodejs-runtimes#segment-runtime-Option) in pages/api.

Previously it only allows config object (https://nextjs.org/docs/app/building-your-application/routing/middleware#matcher), so the single runtime export like `export const runtime = 'edge'` didn't work. PR updates logic to parse config in the module to allow single segment export as well.

It doesn't allow _both_, if config object is exported it'll short-curcuit to read values as config object should able to specify runtime without separate runtime segment.

Closes PACK-1961
---
 .../next-swc/crates/next-core/src/util.rs     | 60 +++++++++++++++++--
 test/turbopack-tests-manifest.json            |  9 ++-
 2 files changed, 60 insertions(+), 9 deletions(-)

diff --git a/packages/next-swc/crates/next-core/src/util.rs b/packages/next-swc/crates/next-core/src/util.rs
index baa18cd58c..381f78a1ce 100644
--- a/packages/next-swc/crates/next-core/src/util.rs
+++ b/packages/next-swc/crates/next-core/src/util.rs
@@ -2,7 +2,7 @@ use anyhow::{bail, Context, Result};
 use indexmap::{IndexMap, IndexSet};
 use serde::{de::DeserializeOwned, Deserialize, Serialize};
 use serde_json::Value as JsonValue;
-use swc_core::ecma::ast::Program;
+use swc_core::ecma::ast::{Expr, Lit, Program};
 use turbo_tasks::{trace::TraceRawVcs, TaskInput, ValueDefault, ValueToString, Vc};
 use turbo_tasks_fs::{rope::Rope, util::join_path, File};
 use turbopack_binding::{
@@ -224,9 +224,11 @@ pub async fn parse_config_from_source(module: Vc<Box<dyn Module>>) -> Result<Vc<
                     .and_then(|export_decl| export_decl.decl.as_var())
                 {
                     for decl in &decl.decls {
-                        if decl
-                            .name
-                            .as_ident()
+                        let decl_ident = decl.name.as_ident();
+
+                        // Check if there is exported config object `export const config = {...}`
+                        // https://nextjs.org/docs/app/building-your-application/routing/middleware#matcher
+                        if decl_ident
                             .map(|ident| &*ident.sym == "config")
                             .unwrap_or_default()
                         {
@@ -246,6 +248,56 @@ pub async fn parse_config_from_source(module: Vc<Box<dyn Module>>) -> Result<Vc<
                                 .emit()
                             }
                         }
+                        // Or, check if there is segment runtime option
+                        // https://nextjs.org/docs/app/building-your-application/rendering/edge-and-nodejs-runtimes#segment-runtime-Option
+                        else if decl_ident
+                            .map(|ident| &*ident.sym == "runtime")
+                            .unwrap_or_default()
+                        {
+                            let runtime_value_issue = NextSourceConfigParsingIssue {
+                                ident: module.ident(),
+                                detail: Vc::cell(
+                                    "The runtime property must be either \"nodejs\" or \"edge\"."
+                                        .to_string(),
+                                ),
+                            }
+                            .cell();
+                            if let Some(init) = decl.init.as_ref() {
+                                // skipping eval and directly read the expr's value, as we know it
+                                // should be a const string
+                                if let Expr::Lit(Lit::Str(str_value)) = &**init {
+                                    let mut config = NextSourceConfig::default();
+
+                                    let runtime = str_value.value.to_string();
+                                    match runtime.as_str() {
+                                        "edge" | "experimental-edge" => {
+                                            config.runtime = NextRuntime::Edge;
+                                        }
+                                        "nodejs" => {
+                                            config.runtime = NextRuntime::NodeJs;
+                                        }
+                                        _ => {
+                                            runtime_value_issue.emit();
+                                        }
+                                    }
+
+                                    return Ok(config.cell());
+                                } else {
+                                    runtime_value_issue.emit();
+                                }
+                            } else {
+                                NextSourceConfigParsingIssue {
+                                    ident: module.ident(),
+                                    detail: Vc::cell(
+                                        "The exported segment runtime option must contain an \
+                                         variable initializer."
+                                            .to_string(),
+                                    ),
+                                }
+                                .cell()
+                                .emit()
+                            }
+                        }
                     }
                 }
             }
diff --git a/test/turbopack-tests-manifest.json b/test/turbopack-tests-manifest.json
index b753b9e5c2..fb21bd4b84 100644
--- a/test/turbopack-tests-manifest.json
+++ b/test/turbopack-tests-manifest.json
@@ -2454,6 +2454,7 @@
   "test/e2e/app-dir/app-middleware/app-middleware.test.ts": {
     "passed": [
       "app dir - middleware without pages dir Updates headers",
+      "app dir - middleware with middleware in src dir works without crashing when using requestAsyncStorage",
       "app-dir with middleware Mutate request headers for Edge Functions Supports draft mode",
       "app-dir with middleware Mutate request headers for Serverless Functions Adds new headers",
       "app-dir with middleware Mutate request headers for Serverless Functions Deletes headers",
@@ -2463,14 +2464,12 @@
       "app-dir with middleware Mutate request headers for next/headers Deletes headers",
       "app-dir with middleware Mutate request headers for next/headers Supports draft mode",
       "app-dir with middleware Mutate request headers for next/headers Updates headers",
-      "app-dir with middleware should filter correctly after middleware rewrite"
-    ],
-    "failed": [
-      "app dir - middleware with middleware in src dir works without crashing when using requestAsyncStorage",
       "app-dir with middleware Mutate request headers for Edge Functions Adds new headers",
       "app-dir with middleware Mutate request headers for Edge Functions Deletes headers",
-      "app-dir with middleware Mutate request headers for Edge Functions Updates headers"
+      "app-dir with middleware Mutate request headers for Edge Functions Updates headers",
+      "app-dir with middleware should filter correctly after middleware rewrite"
     ],
+    "failed": [],
     "pending": [],
     "flakey": [],
     "runtimeError": false